The geometry of magnetic components can affect the incidence of unwanted low frequency radiation in the magnetic field. Gabriel Arianes, David Castillo, Raquel Garcia and Oscar Perez; Ferroxcube, Guadalajara, Spain INTRODUCTION The miniaturization trend has resulted in smaller components and greater board densities in electronic applications. This very density, which … [Read more...]
Design Considerations for Minimizing Large Aperture Effects in Shielding
Large aperture arrays can present special shielding challenges Ron Brewer, Laird Technologies, Delaware Water Gap, PA Shielding can be used at the systems or PC board level to protect sensitive equipment or circuits from both internal and external RF sources. Large systems can be placed in shielded rooms or even shielded buildings. However, regardless of the size of the … [Read more...]
Photonic Bandgap Structures and Their Application to EMC Antennas
PBG structures have been explored as a way of reducing harmonics. Vincente Rodríguez-Pereyra, Ph.D., ETS-Lindgren The concept of photonic structures has recently been applied to the study of the microwave frequency (MW) range [1, 2]. Photonic bandgap (PBG) structures are analogous to a crystal lattice. It is known that in natural crystals there are certain non-occurring or … [Read more...]
Eliminating MYTHS about Printed Circuit Board Power/Ground Plane Decoupling
Bruce Archambeault, Ph. D. IBM Research Triangle Park, NC [email protected] Introduction The use of decoupling capacitors connected between the power and ground planes on a printed circuit board (PCB) is a common practice to help ensure proper functionality and to reduce EMI emissions from printed circuit boards. The proper number of decoupling capacitors, and … [Read more...]
Alternatives in EMI Connectors
There is no generic solution for all problems associated with I/O interfaces ORVILLE HAAS, WILLIAM E. KUNZ SOURCES OF RF INTERFERENCE WITH CLOCK FREQUENCIES of a few gigahertz, today's electronic systems are using pulse edges in the subnanosecond range. Networking interfaces deliver data rates in excess of 100 Mbits/s (Fast Ethernet and FDDI—fiber distributed data interface) … [Read more...]
EMC Design Considerations for Medical Products
Collocation of sensitive medical electronic devices can result in equipment malfunction in medical settings ANTHONY A. DIBIASE INTERACTION BETWEEN MEDICAL products and their electromagnetic environment (EME) presents new challenges to medical device manufacturers, medical service providers, and the regulatory authorities who are responsible for insuring the health and safety … [Read more...]
Impedance Termination of Cable Shields to Reduce EMI Coupling
Surge damage as a result of long cables connected to low voltage data systems can be prevented RICHARD MEININGER & ROBERT BLOUCH This article proposes a solution to the problems encountered when long cables are used to connect low voltage data systems, and either data interference or lightning surge damage is encountered. Three separate interference regimes are addressed: … [Read more...]
EMI Filters for Cardiac Pacemakers and Implantable Defibrillators
The use of ceramic feed-through capacitors, as well as specific filter designs and installation techniques, can make cardiac pacemakers immune to EMI ROBERT A. STEVENSON, Maxwell Technologies Carson City, Nevada, USA Under the coordination of Wireless Technology Research, L.L.C. (WTR), the interaction between cellular phones and cardiac pacemakers has been widely … [Read more...]
Introduction to Measurement Uncertainty for Antenna Calibration
Critical items need to be identified for a particular calibration method MIKE HOWARD The purpose of this article is to introduce the reader to basic elements and concepts in the computation of measurement uncertainty for antenna calibration. Measurement uncertainty is a tool used to account for errors associated with a measurement system. Uncertainty can be used for … [Read more...]
Understanding the Measurement Uncertainties of the Bicon/Log Hybrid Antenna
Surge damage as a result of long cables connected to low voltage data systems can be prevented RICHARD MEININGER & ROBERT BLOUCH Since their first introduction in 1994 at the Roma International Symposium on EMC, bicon/log hybrid antennas have become very popular in EMC labs worldwide. Because there are no band breaks in frequency sweep, test time and effort are reduced. … [Read more...]
